Liberty Bell Tolls

Grissom later admitted at the postflight debriefing
that he was "a bit scared" at liftoff, but he added that he soon gained
confidence along with the g buildup. Hearing the engine roar at the pedestal, he
thought that his elapsed-time clock had started late. Like Shepard, he was
amazed at the smooth quality of the liftoff, but then he noticed gradually more
severe vibrations, never violent enough to impair his vision. To the watchers on
the ground, the Redstone and the capsule appeared to rise slowly and to pass
through a thin, broken cloud window. Then the rocket disappeared, leaving a
contrail that was visible on the beach for about a minute. Grissom's cabin
pressure sealed off at the proper altitude, about 27,000 feet, and he felt
elated that the environmental control system was in good working order. The suit
and cabin temperature, about 57.5 and 97 degrees F, respectively, were quite
comfortable. Watching his instruments for the pitch rate of the Redstone,
Grissom saw it follow directions as programmed, tilting over about one degree
per second.

[371] Under a 3-g load on the up-leg of his flight, Grissom noticed a sudden
change in the color of the horizon from light blue to jet black. His attention
was distracted by the noise of the tower-jettison rocket firing on schedule. The
pilot felt the separation and watched the tower through the window as it drifted
off, trailing smoke, to his right. At two minutes and 22 seconds after launch,
the Redstone's Rocketdyne engine cut off after building a velocity of 6561 feet
per second. Grissom had a strong sensation of tumbling during the transition
from high to zero g, and, while he had become familiar with this sensation in
centrifuge training, for a moment he lost his bearings.

The Redstone coasted for 10 seconds after its engine cut off; then a sharp
report signaled that the posigrade rockets were popping the capsule loose from
the booster. Although Grissom peered out his window throughout his ship's
turnaround maneuver, he never caught sight of his launch vehicle. Angular motion
was perceptible to Grissom only by watching the needle move on the dial or by
seeing an Earth reference by chance. Another cue to the spacecraft's movement
was the Sun's rays, which gradually moved up his torso toward his face,
threatening temporary blindness. Grissom fretted over the automatic turnaround
that should have reversed the capsule faster.

With turnaround accomplished, the Air Force jet pilot for the first time
became a space pilot, assuming manual-proportional control. A constant urge to
look out the window made concentrating on his control tasks difficult. He told
Shepard back in Mercury Control that the panorama of Earth's horizon, presenting
an 800-mile arc at peak altitude, was fascinating. His instruments rated a poor
second to the spectacle below.

Turning reluctantly to his dials and control stick, Grissom made a pitch
movement change but was past his desired mark. He jockeyed the handcontroller
stick for position, trying to damp out all oscillations, then made a yaw
movement and went too far in that direction. By the time the proper attitude was
attained, the short time allocated for these maneuvers had been used, so he
omitted the roll movement altogether. The manual controls impressed Grissom as
very sluggish when compared to the Mercury procedures trainer. Then he switched
to the new rate command control system and found perfect response, although fuel
consumption was high.55

After the pitch and yaw maneuvers, Grissom made a roll-over movement so he
could see the ground from his window. Some land beneath the clouds (later
determined to be western Florida around the Apalachicola area) appeared in the
hazy distance, but the pilot was unable to identify it. Suddenly Cape Canaveral
came into view so clearly that Grissom found it hard to believe that his
slant-range was over 150 miles.

He saw Merritt Island, the Banana River, the Indian River, and what appeared
to be a large airport runway. South of Cape Canaveral, he saw what he believed
to be West Palm Beach. He tried to report to Shepard on the high-frequency [372]
communications circuit every landmark he saw, but his transmissions were not
received. These observations got Grissom behind in his work procedures, as he
realized when he saw the periscope retract.

With Liberty Bell 7 at an altitude of 118.26 miles, it was now time to
position the spacecraft in its reentry attitude. Grissom had initiated the
retrorocket sequence and the capsule was arcing downward. His pulse reached 171
beats per minute.Retrofire gave him the distinct and peculiar feeling that he
had reversed his backward flight through space and was actually moving face
forward. As he plummeted downward, he saw what appeared to be two of the spent
retrorockets pass across the periscope view after the retrorocket package had
been jettisoned.

Pitching the spacecraft over into a reentry attitude of 14 degrees from
Earth-vertical, the pilot tried to see the stars out his observation window.
Instead the glare of sunlight filled his capsule, making it difficult to read
the panel dials, particularly those with blue lights. Grissom felt that he would
not have noticed the .05-g light if he had not known it was about to flash on.

Reentry presented no problem. Grissom could not feel the oscillations
following the g buildup; he could only read them on the rate indicators.
Meanwhile he continued to report to the Mercury Control Center on his electric
current reading, fuel quantity, g loads, and other instrument indications.
Condensation and smoke trailed off the heatshield at about 65,000 feet as
Liberty Bell 7 plunged back into the atmosphere.

The drogue parachute deployed on schedule at 21,000 feet. Grissom said he saw
the deployment and felt some resulting pulsating motion, but not enough to worry
him. Main parachute deployment occurred at 12,300 feet, which was about 1,000
feet higher than the design nominal altitude. Watching the main chute unfurl,
Grissom spotted a six-inch L-shaped tear and another two-inch puncture in the
canopy. Although he worried about them, the holes grew no bigger and his rate of
descent soon slowed to about 28 feet per second. Dumping his peroxide control
fuel, the pilot began transmitting his panel readings.

A "clunk" confirmed that the landing bag had dropped in preparation for
impact. Grissom then removed his oxygen hose and opened his visor but
deliberately left the suit ventilation hose attached. Impact was milder than he
had expected, although the capsule heeled over in the water until Grissom was
lying on his left side. He thought he was facing downward. The capsule gradually
righted itself, and, as the window cleared the water, Grissom jettisoned the
reserve parachute and activated the rescue aids switch. Liberty Bell 7
still appeared watertight, although it was rolling badly with the swells.

Preparing for recovery, he disconnected his helmet and checked himself for
debarkation. The neck dam did not unroll easily; Grissom tinkered with his suit
collar to ensure his buoyancy if he had to get out of the spacecraft quickly.
When the recovery helicopters, which had taken to the air at launch time and
visually followed the contrails and parachute descent, were still about two
miles [373] from the impact point, which was only three miles beyond the
bullseye, Lieutenant James L. Lewis, pilot of the primary recovery helicopter,
radioed Grissom to ask if he was ready for pickup. He replied that he wanted
them to wait five minutes while he recorded his cockpit panel data. Using a
grease pencil with the pressure suit gloves was awkward, and several times the
suit ventilation caused the neck dam to balloon, but the pilot simply placed his
finger between neck and dam to allow the air to escape.

After logging the panel data, Grissom asked the helicopters to begin the
approach for pickup. He removed the pin from the hatch-cover detonator and lay
back in the dry couch. "I was lying there, minding my own business," he said
afterward, "when I heard a dull thud." The hatch cover blew away, and salt water
swished into the capsule as it bobbed in the ocean. The third man to return from
space was faced with the first serious emergency; Liberty Bell 7 was
shipping water and sinking fast.

Grissom had difficulty recollecting his actions at this point, but he was
certain that he had not touched the hatch-activation plunger. He doffed his
helmet, grasped the instrument panel with his right hand, and scurried out the
sloshing hatchway. Floating in the sea, he was thankful that he had unbuckled
himself earlier from most of his harness, including the chest restraints.
Otherwise he might not have been able to abandon ship.

Lieutenant John Reinhard, copilot of the nearest recovery helicopter,
reported afterward that the choppers were making their final approach for
pickup. He was preparing to cut the capsule's antenna whip (according to a new
procedure) with a squib-actuated cutter at the end of a pole, when he saw the
hatch cover fly off, strike the water at a distance of about five feet from the
hatch, and then go skipping over the waves. Next he saw Grissom's head appear,
and the astronaut began climbing through the hatch. Once out, the
pressure-suited spaceman swam away.

Instead of turning his attention to Grissom, Lewis completed his approach to
the sinking spacecraft, as both he and Reinhard were intent on capsule recovery.
This action was a conditioned reflex based on past training experience. While
training off the Virginia beaches the helicopter pilots had noted that the
astronauts seemed at home in and to enjoy the water. So Reinhard quickly clipped
the high-frequency antenna as soon as the helicopter reached Liberty Bell
7. Throwing aside the antenna cutting device, Reinhard picked up the
shepherd's hook recovery pole and carefully threaded the crook through the
recovery loop on top of the capsule. By this time Lewis had lowered the
helicopter to assist Reinhard in his task to a point that the chopper's three
wheels were in the water. Liberty Bell 7 sank out of sight, but the
pickup pole twanged as the attached cable went taut, indicating to the
helicopter pilots that they had made their catch.

Reinhard immediately prepared to pass the floating astronaut the personnel
hoist. But at that moment Lewis called a warning that a detector light had
flashed on the instrument panel, indicating that metal chips were in the oil
sump [375] because of engine strain. Considering the implication of impending
engine failure, Lewis told Reinhard to retract the personnel hoist while he
called the second chopper to retrieve the pilot.

Meanwhile Grissom, having made certain that he was not snared by any lines,
noticed that the primary helicopter was having trouble raising the submerged
spacecraft. He swam back to the capsule to see if he could assist but found the
cable properly attached. When he looked up for the personnel line, he saw the
helicopter start to move away.

Suddenly Grissom realized that he was not riding as high in the water as he
had been. All the time he had been in the water he kept feeling air escape
through the neck dam. The more air he lost, the less buoyancy he had. Moreover,
he had forgotten to secure his suit inlet valve. Swimming was becoming
difficult, and now with the second helicopter moving in he found the rotor wash
between the two aircraft was making swimming more difficult. Bobbing under the
waves, Grissom was scared, angry, and looking for a swimmer from one of the
helicopters to help him tread water. Then he caught sight of a familiar face,
that of George Cox, aboard the second helicopter. Cox was the copilot who had
retrieved both the chimpanzee Ham and Astronaut Shepard. With his head barely
above water, Grissom found the sight of Cox heartening.

Cox tossed the "horse-collar" lifeline straight to Grissom, who immediately
wrapped himself into the sling backwards. Lack of orthodoxy mattered little to
Grissom now, for he was on his way to the safety of the helicopter, even though
swells dunked him twice more before he got aboard. His first thought was to get
a life preserver on. Grissom had been either swimming or floating for a period
of only four or five minutes, "although it seemed like an eternity to me," as he
said afterward.

As the first helicopter moved away from Grissom, it struggled valiantly to
raise the spacecraft high enough to drain the water from the impact bag. Once
the capsule was almost clear of the water, but like an anchor it prevented the
helicopter from moving forward. The flooded Liberty Bell 7 weighed over
5,000 pounds, a thousand pounds beyond the helicopter's lifting capacity. The
pilot, watching his insistent red warning light, decided not to chance losing
two craft in one day. He finally cast loose, allowing the spacecraft to sink
swiftly. Martin Byrnes, aboard the carrier, suggested that a marker be placed at
the point so that the capsule might be recovered later. Rear Admiral J. E. Clark
advised Byrnes that in that area the depth was about 2,800 fathoms.

On the carrier Randolph, examining physicians Strong and Laning, the
same men who had gone over Shepard, found Grissom extremely tired. But the MR-4
astronaut elected to proceed with his preliminary debriefing before going on to
Grand Bahama. The recovery finale, of course, continually intruded in the
discussion. Grissom said he was extremely grateful to Walter Schirra for the
developmental work he had done on the neck dam. He felt that this had saved his
life, although later tests disclosed other difficulties. [376] The debriefing
sessions aboard the Randolph and at Grand Bahama centered on the need for
more egress training (there had been none since April) and the formulation of
specific emergency recovery procedures. Grissom said that he thought he should
have been a little more precise in his attitude control functions. This was a
moot point in view of the sluggishness he had encountered with the manual system
and the apparent play in the control stick linkage. Other than this anomaly, the
spacecraft had performed well; noises of the sequential events had provided good
cues; vibrations had been minimal; the new window had been a delight and should
prove useful on orbital flights; and the environmental control system had
functioned well. But, said Grissom, there were too many couch restraint straps;
the panel lights were too dim; the oxygen consumption rate was high; the urinal
device needed further development; the high-frequency communication circuit was
unsuccessful; and hydrogen peroxide fuel consumption proved to be high on the
rate control system. The last item of that list caused little concern among the
Space Task Group engineers, for they had decided that the rate command mode
would be used primarily for reentry, when fuel economy was less important.

At Grand Bahama, Grissom rested and appeared to have suffered no abnormal
effects from flight into space. The evaluators conceded, however, that the
abnormal recovery experience would have made any such effects difficult to
analyze or to attribute to flight causes. Further questioning of the astronaut
followed the routine established in Shepard's debriefing.56

Obviously one of the major problems to be explained and resolved following
the flight of Liberty Bell 7 was the malfunction of the explosive egress
hatch. Before the mission, Minneapolis-Honeywell had conducted environmental
tests to qualify the hatch and igniter assembly. Although the tests had been run
with the pin installed, conditions had been severe. The component had been
subjected to low and high temperature ranges, a 100-g shock force, and
salt-spray and water-immersion tests. After MR-4, the Space Task Group
established a committee that included Astronaut Schirra to study the hatch
problem. Tests were conducted in an environment even more severe than that used
by the manufacturer, but no premature explosions occurred. Studies were made of
individuals operating the panel switches on the side nearest the actuator; the
clearance margin appeared to be adequate. According to Schirra, "There was only
a very remote possibility that the plunger could have been actuated
inadvertently by the pilot."

The mystery of Grissom's hatch was never solved to everyone's satisfaction.
Among the favorite hypotheses were that the exterior lanyard might have become
entangled with the landing bag straps; that the ring seal might have been
omitted on the detonation plunger, reducing the pressure necessary to actuate
it; or that static electricity generated by the helicopter had fired the hatch
cover. But with the spacecraft and its onboard evidence lying 15,000 feet down
on the bottom of the Atlantic Ocean, it was impossible to determine the true
cause. [377] The only solution was to draft a procedure that would preclude a
recurrence: henceforth the astronaut would not touch the plunger pin until the
helicopter hooked on and the line was taut. As it turned out, Liberty Bell
7 was the last manned flight in Project Mercury in which helicopter
retrieval of the spacecraft was planned. In addition, Grissom would be the only
astronaut who used the hatch without receiving a slight hand injury. As he later
reminded Glenn, Schirra, and Cooper, this helped prove he had not touched his
hatch plunger.57

55 The rate control system consumed about 3
1/2 pounds of hydrogen peroxide in 2 minutes. Based on this usage, if that
system were used exclusively during an orbital mission, all of the control fuel
would be expended in 20 minutes. Grissom's automatic stabilization and control
system worked so slowly during turnaround because, as a later review team
discovered, the one-pound rate thrusters contained some decomposed material.

56 "Postlaunch Memorandum Report for MR-4";
Sjoberg undated memo; Results of the Second U.S. Manned Suborbital
Flight; "Project Mercury Status Report No. 11 for Period Ending July 31,
1961," NASA/STG, 7-9, 26, 30, 31; memo, Richard J. Wisniewski to NASA
Administrator, "Mercury-Redstone-4 Mission," July 24, 1961; memo, John H. Dabbs,
to Chief, Flight Operations Div., STG, "Mercury-Redstone-Four High Frequency
Air/ Ground Communications Test," Aug. 23, 1961; tape of press conference, Cocoa
Beach, Fla., July 22, 1961. Participating with Grissom were James E. Webb, who
awarded the astronaut the NASA Distinguished Service Medal; Leighton I. Davis;
Eberhard F. W. Rees; Robert R. Gilruth; Walter C. Williams; William K. Douglas;
Alan B. Shepard, Jr., and John H. Glenn, Jr. For Grissom's personal account of
the mission, see Dille, ed., We Seven, 205-231. Most of the reports
attribute Grissom's sinking lower in the water during the recovery period to the
open suit inlet valve. The astronaut felt that the loss of buoyancy was caused
by the neck dam. He based his belief on the fact that the dam had been in a
rolled position for some five days; tests conducted later disclosed that the
rolled rubber sets in two days' time, causing a loss of airtight integrity.
Virgil I. Grissom, interview, Houston, April 12, 1965. Also see Virgil I.
Grissom, "It was a Good Flight and a Great Float," Life, LI (July 28,
1961), and Grissom, "Hero Admits He Was Scared," Life, LI (July 28,
1961).

57 Memo, North to Assoc. Administrator,
"Status of MR-4 Hatch Investigation," Aug. 30, 1961; "Postlaunch Memorandum
Report for MR-4." Carpenter, after the second orbital flight, was retrieved from
his raft, being the only other Mercury astronaut to ride a helicopter to a ship.
He, too, was dunked by swells before he was airborne. Grissom expressed his
opinion in an interview on April 12, 1965, that he believed the premature hatch
explosion was caused by the exterior lanyard being loose. At that time it was
held in place by only one screw. Subsequently a better method of securing the
lanyard was effected.